In cellular communication systems, there is a need to supervise the operability of base stations, i.a. with regard to the signal strength prevailing at the transmitters and the associated antennas. If the matching of the antenna changes, for example by sabotage or corrosion, a part of the transmitted power is reflected, causing a drop in the signal strength of the cell and, possibly, damage to the transmitter.
It is therefore of great importance to monitor the antenna performance in order to detect degradation and to secure a good quality of communication.